Subtract 42/84 from 21/18
1st number: 1 3/18, 2nd number: 42/84
21/18 - 42/84 is 2/3.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 84 is 252
Next, find the equivalent fraction of both fractional numbers with denominator 252 - For the 1st fraction, since 18 × 14 = 252,
21/18 = 21 × 14/18 × 14 = 294/252 - Likewise, for the 2nd fraction, since 84 × 3 = 252,
42/84 = 42 × 3/84 × 3 = 126/252 - Subtract the two like fractions:
294/252 - 126/252 = 294 - 126/252 = 168/252 - After reducing the fraction, the answer is 2/3
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